hello - you generally use mapper() and relation() to set up how you'd like your classes to correspond to your table relationships. as far as compound keys, if they are defined with a "primary key" constraint you shouldn't have to worry about them.
if you need to tell a mapper about some other columns that compose its "primary key" other than what the actual table has set up as its primary key, you can use the "primary_key" keyword option on mapper(), such as mapper(SomeClass, sometable, primary_key=[mytable.c.col1]) As for foreign key relations, these are usually represented at the ORM level using the relation() function. the easiest ones are the one-to-many, many-to-one, and many-to-many relationships, which most of your foreign keys are probably defining. for 0.3 these are described here: http://www.sqlalchemy.org/docs/03/datamapping.html#datamapping_relations_onetomany http://www.sqlalchemy.org/docs/03/datamapping.html#datamapping_morerelations a more complex relationship is a "self-referential" relationship, otherwise known as "adjacency list". use this when a single table contains a foreign key relationship pointing to itself: http://www.sqlalchemy.org/docs/03/adv_datamapping.html#advdatamapping_selfreferential finally, the other common mapping is "inheritance", usually "joined table inheritance", where a set of rows are referenced by a base table, but each row also contains additional properties that are added by one of several joined tables, but only one of those tables for each parent row: http://www.sqlalchemy.org/docs/03/adv_datamapping.html#advdatamapping_inheritance_joined good luck ! - mike On Aug 16, 11:59 am, "Lukasz Szybalski" <[EMAIL PROTECTED]> wrote: > Hello, > I am setting up a website with existing database using turbogears. > Database is in mysql. > I am using sqlalchemy but I'm having problems with choosing the mapper? > > There is around 20 tables with a lot of foreign key, compound keys and > alternative keys. > > Which mapper do I use? > Can you point me to the documentation for that as well? > > Thanks, > Lucas --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
